     (is (= {:outputs {[0 0] {:status :success } } :status :success }
            (execute-step {} [(some-ctx-with :step-id [0 0]) some-step-that-sends-failure-on-ch-returns-success]))))
   (testing "that we can pass in a step-results-channel that receives messages with the complete, accumulated step result"
-    (let [step-results-channel (async/chan 100)]
-      (execute-step {} [(some-ctx-with :step-id [0 0]
-                                       :build-number 5
-                                       :step-results-channel step-results-channel
-                                       :pipeline-state-component (noop-pipeline-state/new-no-op-pipeline-state)) some-step-building-up-result-state-incrementally])
+    (let [ctx                  (some-ctx-with :step-id [0 0]
+                                              :build-number 5
+                                              :pipeline-state-component (noop-pipeline-state/new-no-op-pipeline-state))
+          step-results-channel (step-result-updates-for ctx)]
+      (execute-step {} [ctx some-step-building-up-result-state-incrementally])
     (is (= [{:build-number 5 :step-id [0 0] :step-result {:status :running } }
             {:build-number 5 :step-id [0 0] :step-result {:status :running :out "hello"} }
             {:build-number 5 :step-id [0 0] :step-result {:status :running :out "hello world"} }

    (let [ctx (some-ctx-with :step-id [0 0]
                             :build-number 5
                             :pipeline-state-component (noop-pipeline-state/new-no-op-pipeline-state))
          step-results-channel (-> (event-bus/subscribe ctx :step-result-updated)
                                   (event-bus/only-payload)
                                   (buffered))]
      (execute-step {} [ctx some-step-building-up-result-state-incrementally])
    (is (= [{:build-number 5 :step-id [0 0] :step-result {:status :running } }
            {:build-number 5 :step-id [0 0] :step-result {:status :running :out "hello"} }

  (testing "that the event bus is notified when a step finishes"
    (let [ctx (some-ctx-with :build-number 3
                             :step-id [1 2 3])
          step-finished-events (step-finished-events-for ctx)]
      (execute-step {} [ctx some-other-step])
      (is (= [{:build-number 3
               :step-id [1 2 3]
